Left Ventricular Non-Compaction
Non-compaction cardiomyopathy (NCC), also called spongiform cardiomyopathy, is a rare congenital cardiomyopathy that affects both children and adults. (Pignatelli R H, McMahon C J, Dreyer W J, et al (November 2003). “Clinical characterization of left ventricular noncompaction in children: a relatively common form of cardiomyopathy.” Circulation 108 (21): 2672-8.) It results from the failure of myocardial development during embryogenesis. (Espinola-Zavaleta, Nilda; Soto, Elena; Castellanos, Luis Munoz; Játiva-Chávez, Silvio; Keirns, Candace. (2006). “Non-compacted Cardiomyopathy: Clinical-Echocardiographic Study” Cardiovasc. Ultrasound 4 (1): 35).
During development, the majority of the heart muscle is a sponge-like meshwork of interwoven myocardial fibers. As normal development progresses, these trabeculated structures undergo significant compaction that transforms them from spongy to solid. This process is particularly apparent in the ventricles, and particularly so in the left ventricle. Noncompaction cardiomyopathy results when there is failure of this process of compaction. Because the consequence of non-compaction is particularly evident in the left ventricle, the condition is also called left ventricular noncompaction (LVNV). LVNC is a cardiomyopathy characterized anatomically by deep trabeculations in the ventricular wall, which define recesses communicating with the main ventricular chamber. Other hypotheses and models have been proposed, none of which is as widely accepted as the noncompaction model.
Current diagnostic criteria for left ventricular non-compaction (LVNC) are controversial and often poorly correlate with outcomes. (A Cardiac Magnetic Resonance Imaging (cMRI) Based Approach to Diagnosis and Quantification of LV Non-compaction Using Relative Signal Intensities Top of Form P. Choudhary, S. Grieve, C. Semsarian, D. Richmond, D. Celermajer, R. Puranik Heart, Lung and Circulation Volume 22, Supplement 1, Page S162, 2013).
Dilated Cardiomyopathy
There are several different types of cardiomyopathy. Dilated cardiomyopathy (DC) is the most common form. Dilated cardiomyopathy is a disease of the heart muscle, primarily affecting your heart's main pumping chamber (left ventricle). The left ventricle becomes enlarged (dilated) and can't pump blood to your body with as much force as a healthy heart can.
Dilated cardiomyopathy doesn't necessarily cause symptoms, but for some people the disease is life-threatening. Dilated cardiomyopathy is a common cause of heart failure, the inability of the heart to supply the body's tissue and organs with enough blood. Dilated cardiomyopathy may also cause irregular heartbeats (arrhythmia), blood clots or sudden death.
Dilated cardiomyopathy may affect people of all ages, including infants and children. Treatments may be available for the underlying cause of dilated cardiomyopathy, or to improve blood flow and reduce symptoms.
Most people who have heart failure need to take medicines. Some medicines treat symptoms. Others may help prevent your heart failure from becoming worse or may prevent other heart problems.
Current Treatment for Left Ventricular Non-Compaction and Dilated Cardiomyopathy
So far only management programs similar to management programs for other types of cardiomyopathies are available which include the use of angiotensin-converting enzyme (ACE) inhibitors to improve your heart's pumping capability, such as enalapril (Vasotec), lisinopril (Zestril, Prinivil), ramipril (Altace) and captopril (Capoten); angiotensin receptor blockers (ARBs) for those who can't take ACE inhibitors, such as losartan (Cozaar) and valsartan (Diovan); beta blockers to improve heart function, such as carvedilol (Coreg) and metoprolol (Lopressor, Toprol-XL); digoxin (Lanoxin) also referred to as digitalis, increases the strength of your heart muscle contractions and also tends to slow the heartbeat. Digoxin reduces heart failure symptoms and improves your ability to live with cardiomyopathy; diuretics to increase urination and keep fluid from collecting in your body. Commonly prescribed diuretics for heart failure include bumetanide (Bumex) and furosemide (Lasix). The drugs also decrease fluid in your lungs, so you can breathe more easily. One diuretic, spironolactone (Aldactone), may also be helpful in treating scarring of your heart tissue.
Another option for some people with dilated cardiomyopathy is a special pacemaker that coordinates the contractions between the left and right ventricles (biventricular pacing). In people who may be at risk of serious arrhythmias, drug therapy or an implantable cardioverter-defibrillator (ICD) may be options. An ICD is a small device—about the size of a box of matches—implanted in your chest to continuously monitor your heart rhythm and deliver electrical shocks when needed to control abnormal, rapid heartbeats. The device can also work as a pacemaker. In severe cases, Heart bypass (CABG) surgery or angioplasty to improve blood flow to the damaged or weakened heart muscle or Valve replacement or repair might be necessary. Chronic heart failure becomes worse over time. Many people who have heart failure will die from the condition. Heart failure is most often a chronic illness, which may get worse over time. Some people develop severe heart failure, in which medicines, other treatments, and surgery no longer help. Many people are at risk for deadly heart rhythms, and may need medicines or a defibrillator.
A heart transplant may be recommended for patients who have failed all the standard treatments and still have very severe symptoms as well as placement of a left ventricular assist device or artificial heart. However, there remains a need in the art for compositions and methods for treatment of left ventricular non-compaction and dilated cardiomyopathies.